JP2014208432A - Decorative sheet and decorative resin molded article - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a decorative sheet having three-dimensional molding property that can sufficiently follow features of a decorative resin molded article having a complicated surface shape.SOLUTION: The decorative sheet is composed of a laminate having at least a substrate layer, a primer layer, and a metal thin film layer, layered in this order, in which the primer layer contains a cured product of a resin having a glass transition point of -30°C to 80°C.

Description

  The present invention relates to a decorative sheet having a metallic design. Furthermore, the present invention relates to a decorative resin molded product using the decorative sheet.

  2. Description of the Related Art Conventionally, in order to impart a metallic design to vehicle interior / exterior parts, building material interior materials, home appliance housings, and the like, members obtained by applying metal plating, metal coating, etc. to the resin surface have been used. However, when performing metal plating, metal coating, etc., it is necessary to take measures against waste water containing metal, solvent vapor, and the like. In general, the yield of these members is not good.

  Therefore, in recent years, a decorative resin molded product in which a decorative sheet having a metallic tone is laminated on the surface of a resin molded product is used as these members. For the production of a decorative resin molded product, a molding method in which a decorative sheet to which a design has been applied in advance is integrated with a resin by injection molding is used.

  Some decorative resin molded products have a complicated surface shape such as a three-dimensional curved surface. For this reason, the decorative sheet is required to have three-dimensional formability that can sufficiently follow the shape of the decorative resin molded product having a complicated surface shape. In particular, in a decorative sheet having a metallic tone, low adhesion between a resin layer (for example, a base material layer and an adhesive layer) formed of a resin and a metal thin film layer formed of a metal tends to be a problem. Due to the low adhesion between the resin layer and the metal thin film layer, the resin layer and the metal thin film layer may be peeled off and floated when the decorative sheet is formed.

  For example, Patent Document 1 discloses that a post-anchor layer formed of a resin is provided in order to improve the adhesion between the metal vapor deposition layer of the metal vapor deposition transfer material and the adhesive printing layer. However, in recent years, there has been a demand for a decorative sheet that can follow the shape of a particularly complex decorative resin molded product. Such a decorative sheet has a maximum draw ratio, for example, in a portion corresponding to a curved portion of the resin molded product. May be stretched to 150% or more. This means that a part of the decorative sheet having the metal thin film layer is stretched by 2.5 times or more, which is a very strict molding condition. For this reason, the conventional decorative sheet having a metal thin film layer cannot follow the shape of such a complicated decorative resin molded product, and the resin layer and the metal thin film layer can be used during the molding of the decorative sheet. There is a problem that peeling occurs between the two and the like, and floating occurs.

  Under such circumstances, there is a demand for a decorative sheet having a three-dimensional formability that can sufficiently follow the shape of a decorative resin molded product having a complicated surface shape.

Japanese Patent No. 3127398

  The main object of the present invention is to provide a decorative sheet having high three-dimensional formability that can sufficiently follow the shape of a decorative resin molded product having a complicated surface shape.

  The present inventor has intensively studied to solve the above problems. As a result, in the decorative sheet comprising a laminate in which the base material layer, the primer layer, and the metal thin film layer are laminated in this order, the primer layer is a cured product of a resin having a glass transition point of −30 ° C. to 80 ° C. It was found that high three-dimensional moldability capable of sufficiently following the shape of a decorative resin molded product having a complicated surface shape can be imparted to the decorative sheet. The present invention has been completed by further studies based on these findings.

That is, this invention provides the invention of the aspect hung up below.
Item 1. At least, a base material layer, a primer layer, and a metal thin film layer are composed of a laminated body laminated in this order,
The primer layer is a decorative sheet containing a cured product of a resin having a glass transition point of −30 ° C. to 80 ° C.
Item 2. Used for decorating resin molded products with curved parts,
Item 2. The decorative sheet according to Item 1, wherein the curved portion has a shape that requires stretching at a maximum stretching ratio of 150% or more with respect to the decorative sheet.
Item 3. Item 1 or 2 wherein the resin having a glass transition point of −30 ° C. to 80 ° C. is at least one selected from the group consisting of polyester resins, polyurethane resins, polyacrylic resins, and polyolefin resins. The decorative sheet as described.
Item 4. The resin having a glass transition point of −30 ° C. to 80 ° C. is a polyol resin,
Item 4. The decorative sheet according to any one of Items 1 to 3, wherein the primer layer is formed of a cured product of the polyol resin and an isocyanate compound.
Item 5. Item 5. The decorative sheet according to Item 4, wherein the polyol resin is a polyester polyol.
Item 6. Item 6. The decorative sheet according to Item 4 or 5, wherein the isocyanate compound is an aliphatic isocyanate compound.
Item 7. Item 7. The decorative sheet according to any one of Items 1 to 6, which has an adhesive layer between the base material layer and the primer layer.
Item 8. Item 8. The decorative sheet according to Item 7, wherein the adhesive layer contains a chlorine-based resin.
Item 9. The metal thin film layer is formed of at least one metal selected from the group consisting of tin, indium, chromium, aluminum, nickel, copper, silver, gold, platinum, zinc, and an alloy containing at least one of these. Item 9. The decorative sheet according to any one of Items 1 to 8.
Item 10. Item 10. The decorative sheet according to any one of Items 1 to 9, wherein a surface protective layer is further laminated on the metal thin film layer.
Item 11. Item 11. The decorative sheet according to any one of Items 1 to 10, wherein a transparent film layer is further laminated on the metal thin film layer.
Item 12. Item 12. The decorative sheet according to any one of Items 1 to 11, wherein the primer layer further contains a colorant.
Item 13. At least a molded resin layer, a base material layer, a primer layer, and a laminated body in which a metal thin film layer is laminated in this order,
The primer layer is a decorative resin molded product including a cured product of a resin having a glass transition point of −30 ° C. to 80 ° C.
Item 14. The vacuum forming process which shape | molds the decorating sheet in any one of claim | items 1-12 in a solid shape beforehand with a vacuum forming die,
Trimming step of trimming an excess portion of the vacuum-decorated decorative sheet to obtain a molded sheet, and inserting the molded sheet into an injection mold, closing the injection mold, and injecting the resin in a fluid state into the injection mold An integration step of injecting the resin into the mold and integrating the resin and the molded sheet;
A method for producing a decorated resin molded product.
Item 15. The decorative resin molded product has a curved portion;
Item 15. The method for producing a decorated resin molded article according to Item 14, wherein in at least one of the vacuum forming step and the integration step, the decorative sheet positioned at the curved portion is stretched to a maximum draw ratio of 150% or more.

  According to the decorative sheet of the present invention, a decorative sheet having high three-dimensional formability that can sufficiently follow the shape of a decorative resin molded product having a complicated surface shape, and the decorative sheet are used. A decorative resin molded product can be provided.

It is a schematic sectional drawing of an example of the decorating sheet which concerns on this invention. It is a schematic sectional drawing of an example of the decorating sheet which concerns on this invention. It is a schematic sectional drawing of an example of the decorating sheet which concerns on this invention. It is a schematic sectional drawing of an example of the decorating sheet which concerns on this invention. It is the surface photograph after the heat test of the decorative resin molded product manufactured using the decorative sheet obtained in Example 1. It is the surface photograph after the heat test of the decorative resin molded product manufactured using the decorative sheet obtained in Comparative Example 1.

1. Decorating sheet The decorating sheet of the present invention comprises a laminate in which at least a base material layer, a primer layer, and a metal thin film layer are laminated in this order, and the primer layer has a glass transition point of −30 ° C. to 30 ° C. A cured product of a resin at 80 ° C. is included. In the decorative sheet of the present invention, the primer layer provided between the base material layer and the metal thin film layer includes a cured product of the resin having the specific glass transition point as described above, so that it is complicated. High three-dimensional moldability that can sufficiently follow the shape of a decorative resin molded product having a surface shape is imparted. Hereinafter, the decorative sheet of the present invention will be described in detail.

Laminated structure of decorative sheet The decorative sheet of the present invention has a laminated structure having at least a base material layer 1, a primer layer 3, and a metal thin film layer 4 in this order. In the decorative sheet of the present invention, an adhesive layer 2 may be provided between the base material layer 1 and the primer layer 3 as necessary for the purpose of improving the adhesion between these layers. Moreover, you may provide the surface protective layer 5 on the metal thin film layer 4 as needed for the purpose of improving the damage resistance of a decorating sheet, a weather resistance, etc. In addition, a second primer layer 6 may be provided under the surface protective layer 5 as necessary for the purpose of improving the adhesion between the surface protective layer 5 and the layer formed thereunder. Good. A color clear layer 7 may be provided on the metal thin film layer 4 as necessary for the purpose of further imparting gloss to the metal tone of the metal thin film layer 4. When the color clear layer 7 is provided, a third primer layer 8 may be provided between the metal thin film layer 5 and the color clear layer 7 as necessary. Moreover, on the metal thin film layer 4, you may provide the transparent film layer 9 etc. as needed for the purpose of improving the moldability of a decorating sheet. Furthermore, a second adhesive layer 10 or the like may be provided under the base material layer 1.

  As a laminated structure of the decorative sheet of the present invention, a laminated structure in which a base layer / primer layer / metal thin film layer is laminated in this order; a laminated layer in which an adhesive layer / base material layer / primer layer / metal thin film layer is laminated in this order. Structure: Laminated structure in which base layer / adhesive layer / primer layer / metal thin film layer is laminated in this order; Laminated structure in which base layer / adhesive layer / primer layer / metal thin film layer / surface protective layer is laminated in this order; Laminated structure in which base material layer / adhesive layer / primer layer / metal thin film layer / second primer layer / surface protective layer are laminated in this order; base material layer / adhesive layer / primer layer / metal thin film layer / color clear layer / Laminated structure in which second primer layer / surface protective layer is laminated in this order; base material layer / adhesive layer / primer layer / metal thin film layer / third primer layer / color clear layer / second primer layer / surface protection The layers are stacked in this order Laminated structure: Laminated structure in which base layer / adhesive layer / primer layer / metal thin film layer / transparent film layer / third primer layer / color clear layer / second primer layer / surface protective layer are laminated in this order; Laminated structure in which material layer / adhesive layer / primer layer / metal thin film layer / transparent film layer / second primer layer / surface protective layer are laminated in this order; base material layer / adhesive layer / primer layer / metal thin film layer / transparent Examples include a laminated structure in which film layers / surface protective layers are laminated in this order; a laminated structure in which base material layers / adhesive layers / primer layers / metal thin film layers / transparent film layers are laminated in this order.

  FIG. 1 is a schematic cross-sectional view of an example of a decorative sheet in which a base layer / adhesive layer / primer layer / metal thin film layer / surface protective layer are laminated in this order as an embodiment of the laminated structure of the decorative sheet of the present invention. The figure is shown. FIG. 2 shows a decorative sheet in which a base layer / adhesive layer / primer layer / metal thin film layer / second primer layer / surface protective layer are laminated in this order as an embodiment of the laminated structure of the decorative sheet of the present invention. FIG. 2 shows a schematic cross-sectional view of an example. In FIG. 3, as one aspect of the laminated structure of the decorative sheet of the present invention, a base layer / adhesive layer / primer layer / metal thin film layer / third primer layer / color clear layer / second primer layer / surface protection The schematic sectional drawing of an example of the decorating sheet | seat on which the layer was laminated | stacked in this order is shown. In FIG. 4, as one aspect of the laminated structure of the decorative sheet of the present invention, a base layer / adhesive layer / primer layer / metal thin film layer / transparent film layer / third primer layer / color clear layer / second primer The schematic sectional drawing of an example of the decorating sheet | seat on which the layer / surface protective layer was laminated | stacked in this order is shown.

Composition of each layer forming the decorative sheet [base material layer 1]
The base material layer 1 is formed of a resin sheet (resin film) that plays a role as a support in the decorative sheet of the present invention. The resin component used for the base material layer 1 is not particularly limited, and may be appropriately selected according to the three-dimensional moldability, compatibility with the molded resin layer, and the like, and preferably a thermoplastic resin. Specific examples of the thermoplastic resin include acrylonitrile-butadiene-styrene resin (hereinafter sometimes referred to as “ABS resin”); acrylonitrile-styrene-acrylic ester resin; acrylic resin; polyolefins such as polypropylene and polyethylene Resin; polycarbonate resin; vinyl chloride resin; polyethylene terephthalate (PET). Among these, ABS resin is preferable from the viewpoint of three-dimensional moldability. As a resin component which forms the base material layer 1, only 1 type may be used and 2 or more types may be mixed and used. Moreover, the base material layer 1 may be formed with the single layer sheet | seat of these resin, and may be formed with the multilayer sheet | seat by the same kind or different kind | species resin. In addition, although the method of improving the three-dimensional moldability of a decorating sheet by making the base material layer 1 into a multilayer sheet is considered, in the decorating sheet of this invention, since it has the specific primer layer 3 mentioned later. Even if the base material layer 1 is a single layer sheet, it has high three-dimensional formability.

  The base material layer 1 is subjected to physical or chemical surface treatment such as an oxidation method or an unevenness method on one side or both sides as required in order to improve the adhesion with the primer layer 3 or the adhesive layer 2 described later. It may be given. Examples of the oxidation method performed as the surface treatment of the base material layer 1 include a corona discharge treatment, a plasma treatment, a chromium oxidation treatment, a flame treatment, a hot air treatment, and an ozone ultraviolet treatment method. Moreover, as the uneven | corrugated method performed as surface treatment of the base material layer 1, a sandblasting method, a solvent processing method, etc. are mentioned, for example. These surface treatments are appropriately selected according to the type of the resin component constituting the base material layer 1, and preferably a corona discharge treatment method from the viewpoints of effects and operability.

  In addition, the base material layer 1 may be colored with a colorant or the like, painted for adjusting the color, formation of a pattern for imparting design properties, or the like.

  The thickness of the base material layer 1 is not particularly limited and is appropriately set according to the use of the decorative sheet, etc., but is usually about 50 to 800 μm, preferably about 100 to 600 μm, more preferably about 200 to 500 μm. Can be mentioned. When the thickness of the base material layer 1 is within the above range, the decorative sheet can be provided with more excellent three-dimensional formability, designability, and the like.

[Adhesive layer 2]
The adhesive layer 2 is a layer provided between the base material layer 1 and the metal thin film layer 4 as necessary in order to improve the adhesion between the base material layer 1 and a primer layer 3 described later.

  The resin for forming the adhesive layer 2 is not particularly limited as long as it can improve the adhesion between the base material layer 1 and the primer layer 3, and examples thereof include a thermoplastic resin. The thermoplastic resin is not particularly limited. For example, acrylic resin; polyolefin resin such as polypropylene and polyethylene; polycarbonate resin; ABS resin; polyester resin such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN); , Polyvinyl chloride resins such as chlorinated polyethylene, polyvinylidene chloride, ethylene-vinyl chloride copolymer, vinyl chloride-vinyl acetate copolymer, vinyl chloride-vinyl acetate- (meth) acrylic copolymer, polypropylene chloride And chlorinated resins such as chlorinated polypropylene. As the resin for forming the adhesive layer 2, an acrylic resin or a chlorine-based resin is preferably used from the viewpoint of improving the adhesion between the base material layer 1 and the primer layer 3. As the chlorine-based resin, from the viewpoint of enhancing the adhesion between the base material layer 1 and the primer layer 3, a vinyl chloride resin and a vinyl chloride-vinyl acetate copolymer are preferable, and vinyl chloride-acetic acid is more preferable. A vinyl copolymer is mentioned. As resin which forms the contact bonding layer 2, you may use individually by 1 type, and may mix and use 2 or more types. In the present invention, “(meth) acryl” is a general term for “acryl” and “methacryl”, and other similar things with (meth) have the same meaning.

  For example, when using a mixed resin of an acrylic resin and a chlorine-based resin as the resin that forms the adhesive layer 2, the resin that forms the adhesive layer 2 from the viewpoint of improving the adhesion between the base material layer 1 and the primer layer 3 The mass ratio between the acrylic resin and the chlorine-based resin is preferably about 20/80 to 80/20, and more preferably about 30/70 to 70/30.

  Chlorine resin is suitable as a resin for forming the adhesive layer 2 in that high adhesion can be obtained, but has a problem that the metal constituting the metal thin film layer is oxidized to cause the metal thin film layer to fade. However, in the present invention, since a primer layer 3 to be described later is disposed between the adhesive layer 2 and the metal thin film layer 4, even when a chlorine-based resin is used as the resin for forming the adhesive layer 2, the metal The fading of the thin film layer 4 is suppressed.

  When the adhesive layer 2 contains a chlorine resin, the acid value of the chlorine resin is not particularly limited, but from the viewpoint of further improving the adhesion between the base material layer 1 and the primer layer 3, it may be 1 mgKOH / g or more. Preferably, it is 4 mgKOH / g or more, more preferably 6 mgKOH / g. In the present invention, the metal thin film layer 4 is protected by the primer layer 3 as described above even when the adhesive layer 2 is formed of a highly oxidized chlorine-based resin, for example, a chlorine-based resin whose oxidation exceeds 6 mgKOH. While suppressing fading of the metal thin film layer 4, the base material layer 1 and the metal thin film layer 4 can be bonded with high adhesion, and the three-dimensional formability of the decorative sheet can be enhanced. However, since the fading of the metal thin film layer 4 may be promoted if the acid value of the chlorinated resin is too large, it is usually preferably 12 mgKOH / g or less.

  When the adhesive layer 2 is provided, the thickness of the adhesive layer 2 is not particularly limited. However, from the viewpoint of improving the adhesion between the base material layer 1 and a primer layer 3 described later, about 0.6 to 3.5 μm, preferably It can be about 1 to 2 μm.

  The method for forming the adhesive layer 2 is not particularly limited. The adhesive layer 2 can be formed, for example, by applying the above-mentioned resin on the surface of either the base material layer 1 or the primer layer 3 described later, and heat sealing or dry lamination.

[Primer layer 3]
The primer layer 3 is provided to give the decorative sheet of the present invention a high three-dimensional formability and to provide a decorative sheet that can sufficiently follow the shape of the decorative resin molded product having a complicated surface shape. It is a layer. Specifically, when the primer layer 3 is used for a decorative application of a resin molded product in which the decorative sheet of the present invention has a curved portion, the curved portion has, for example, the decorative sheet of the present invention, for example, Even if it is a shape that requires stretching at a maximum draw ratio of 150% or more, and further about 200%, it is provided in order to be able to follow such a shape. In this invention, the said primer layer 3 is characterized by including the hardened | cured material of resin whose glass transition point (Tg) is -30 degreeC-80 degreeC, According to such a characteristic, it is the said with respect to a decoration sheet | seat. Such a high three-dimensional formability is imparted. The upper limit of the maximum draw ratio is preferably about 250%.

  The primer layer 3 has a function of bringing the base material layer 1 and the metal thin film layer 4 into close contact with each other. When the adhesive layer 2 is provided between the base material layer 1 and the primer layer 3, the adhesive layer 2 adheres the base material layer 1 and the primer layer 3, and the primer layer 3 is the adhesive layer. 2 and the metal thin film layer 4 are in close contact with each other. As described above, in the present invention, since the primer layer 3 is disposed so that the adhesive layer 2 and the metal thin film layer 4 are not in direct contact with each other, the adhesive layer 2 and the metal thin film layer 4 are directly connected to each other. Discoloration of the metal thin film layer 4 caused by contact can be effectively prevented.

  From the viewpoint of further improving the three-dimensional formability of the decorative sheet, the primer layer 3 preferably includes a cured product of a resin having a glass transition point of -20 to 70 ° C, more preferably a glass transition point of -10 to 40 ° C. The hardened | cured material of this resin is included, More preferably, the hardened | cured material of resin whose glass transition point is 0-20 degreeC is included. If the glass transition point of the resin contained in the primer layer 3 is too low, the adhesiveness with the metal thin film layer 4 is lowered, and peeling or floating may occur between the layers due to heating during molding of the decorative sheet. Furthermore, when the adhesive layer 2 contains a chlorine-based resin, the metal thin film layer 4 tends to fade. On the other hand, if the glass transition point of the resin contained in the primer layer 3 is too high, the primer layer 3 is thermally contracted due to heating at the time of molding the decorative sheet, and peeling or floating occurs between the layers of the decorative sheet. There is. In the present invention, the glass transition point (Tg) is a value obtained by differential scanning calorimetry (DSC) based on JIS K7121-1987.

  Among the resins that are cured to form the primer layer 3, the content of the resin having a glass transition point (Tg) of −30 ° C. to 80 ° C. is preferably 50% by mass or more, more preferably 70% by mass or more. Preferably 90% or more is mentioned. The resin that is cured to form the primer layer 3 is particularly preferably only a resin having a glass transition point (Tg) of −30 ° C. to 80 ° C.

  The resin that is cured to form the primer layer 3 has a glass transition point (Tg) in the range of −30 ° C. to 80 ° C. and can be cured by drying, chemical reaction, or the like to form a coating film. For example, a thermosetting resin, a thermoplastic resin, and the like are preferable, and a polyester resin, a polyurethane resin, a polyacrylic resin, a polyolefin resin, and the like are preferable. The resin contained in the primer layer 3 is more preferable from the viewpoint of suppressing the fading of the metal thin film layer 4 when the adhesive layer 2 contains a chlorine-based resin while further improving the three-dimensional formability of the decorative sheet. May include polyester resins. A resin having a glass transition point (Tg) of −30 ° C. to 80 ° C. may be used alone or in combination of two or more.

  The polyester-based resin, polyurethane-based resin, polyacrylic resin, and polyolefin-based resin are not particularly limited. However, the three-dimensional formability of the decorative sheet is improved, and the adhesive layer 2 contains a chlorine-based resin. From the viewpoint of suppressing fading of the metal thin film layer 4, for example, a polyester polyol that is a polyester resin; a urethane polyol that is a polyurethane resin, such as a polyester urethane polyol or an acrylic urethane polyol; an acrylic polyol that is a polyacrylic resin; Examples of the polyolefin resin include polyolefin polyols such as polyethylene polyol, polypropylene polyol, polybutadiene polyol, and polyisoprene polyol.

  Examples of the polyester polyol include a condensed polyester diol obtained by reacting a low molecular diol and a dicarboxylic acid, a polylactone diol obtained by ring-opening polymerization of a lactone, and a polycarbonate diol. Examples of the dicarboxylic acid include aliphatic dicarboxylic acids such as succinic acid, adipic acid, sebacic acid, glutaric acid, azelaic acid, maleic acid and fumaric acid, and aromatic dicarboxylic acids such as terephthalic acid and isophthalic acid. As the lactone, for example, ε-caprolactone is used. Specific examples of the polyester polyol include polyethylene adipate, polybutylene adipate, polyhexamethylene adipate, polyneopentyl adipate, polyethylene butylene adipate, polybutylene hexabutylene adipate, polydiethylene adipate, poly (polytetramethylene ether) adipate, polyethylene adipate Examples thereof include zetate, polyethylene sebacate, polybutylene azate, polybutylene sebacate, polyhexamethylene carbonate diol, and the like.

  The primer layer 3 of the present invention is preferably formed of a cured product of the above resin having a glass transition point (Tg) of −30 ° C. to 80 ° C. and a curing agent. Moreover, the primer layer 3 of the present invention is formed of a reaction-curable urethane resin obtained by a polyol resin having a glass transition point (Tg) of −30 ° C. to 80 ° C. and a curing agent made of an isocyanate compound or the like. More preferably. The polyol resin having a glass transition point (Tg) of −30 ° C. to 80 ° C. is not particularly limited and is, for example, the polyester resin, polyurethane resin, polyacrylic resin, or polyolefin resin exemplified above. And polyols.

  Examples of the isocyanate compound include 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, xylene-1,4-diisocyanate, xylene-1,3-diisocyanate, 4,4'-diphenylmethane diisocyanate, 2,4. '-Diphenylmethane diisocyanate, 2,2'-diphenylmethane diisocyanate, 4,4'-diphenyl ether diisocyanate, polymethylene polyphenylene polyisocyanate, 2-nitrodiphenyl-4,4'-diisocyanate, 2,2'-diphenylpropane-4,4 '-Diisocyanate, 3,3'-dimethyldiphenylmethane-4,4'-diisocyanate, 4,4'-diphenylpropane diisocyanate, m-phenylene diisocyanate, p-phenylene Aromatic isocyanates such as isocyanate, naphthylene-1,4-diisocyanate, naphthylene-1,5-diisocyanate, 3,3′-dimethoxydiphenyl-4,4′-diisocyanate; 1,4-diisocyanatobutane, 1,5 -Diisocyanatopentane, 1,6-diisocyanatohexane (1,6-hexamethylene diisocyanate, HDI), 1,6-diisocyanato-2,2,4-trimethylhexane, 2,6-diisocyanatohexanoic acid Aliphatic isocyanates such as methyl (lysine diisocyanate); alicyclic diisocyanates such as isophorone diisocyanate, hydrogenated xylylene diisocyanate, and hydrogenated diphenylmethane diisocyanate. Among these, aliphatic isocyanate is preferable from the viewpoint of suppressing peeling between layers due to heating during molding of the decorative sheet. A hardening | curing agent may be used individually by 1 type, and may be used in combination of 2 or more types.

  When using the above curing agent for the primer layer 3, the content of the curing agent is not particularly limited, but fading the metal thin film layer 4 while improving the adhesion between the base material layer 1 and the metal thin film layer 4. From the viewpoint of effectively suppressing, the amount is preferably about 1 to 15 parts by mass, more preferably about 3 to 10 parts by mass with respect to 100 parts by mass of the resin forming the primer layer 3.

  Such a reaction curable urethane resin forming the primer layer 3 may be either a one-component curable type or a two-component curable type, preferably a two-component curable type.

  In addition, it is preferable that the primer layer 3 does not contain chlorine resin substantially from a viewpoint of suppressing the fading of the metal thin film layer 4 more effectively. In addition, in this invention, the primer layer 3 does not contain a chlorine-type resin substantially, for example, it means that the ratio of the chlorine-type resin contained in the primer layer 3 is 1 mass% or less. Moreover, it is preferable that the acid value of resin which forms the primer layer 3 is 6 mgKOH / g or less.

  The primer layer 3 may further contain a colorant in addition to the above resin for the purpose of adjusting the color of the decorative sheet or improving the design. In particular, when the primer layer 3 includes a colorant having the same color as that of the metal thin film layer 4, for example, even when the metal thin film layer 4 is discolored, it is possible to effectively suppress a decrease in the metallic design of the decorative sheet. Can do. What is necessary is just to select suitably what can exhibit a metallic tone with the metal thin film layer 4 by mix | blending with the primer layer 3 as such a coloring agent, For example, a pigment, dye, etc. can be used. . Specific examples of colorants include carbon black (black), iron black, titanium white (titanium oxide), antimony white, yellow lead, titanium yellow, petal, cadmium red, ultramarine, cobalt blue, and other inorganic pigments, quinacridone red Organic pigments or dyes such as isoindolinone yellow and phthalocyanine blue, metallic pigments composed of scaly foils such as aluminum and brass, pearl luster composed of scaly foils such as titanium dioxide-coated mica and basic lead carbonate (pearl) ) Pigments. In order to color the primer layer 3 in a metallic tone, for example, a black colorant such as carbon black may be used in combination with a white colorant such as titanium oxide. Further, it is also preferable to add a colorant of another system according to the type of metal forming the metal thin film layer 4 so as to exhibit a color closer to the metal thin film layer 4. For example, tin and chromium have a yellowish metallic tone, so when these metals are used, a yellow colorant may be further added, and indium and aluminum have a pale metallic tone. When using these metals, a blue colorant may be further added. From the viewpoint of achieving both the adhesion between the primer layer 3 and the metal thin film layer 4 and the fading resistance of the metal thin film layer 4, the mass ratio of the resin forming the primer layer 3 to the colorant (resin: colorant) Is preferably about 90:10 to 60:40, more preferably about 80:20 to 70:30.

  Although the thickness in particular of the primer layer 3 is not restrict | limited, From a viewpoint of improving the three-dimensional moldability of a decorating sheet, Preferably it is about 0.5-3 micrometers, More preferably, about 1-2 micrometers is mentioned.

  The primer layer 3 is formed using a primer composition containing the above resin. Specifically, the primer layer 3 is a solid coating by a gravure coat, a gravure reverse coat, a gravure offset coat, a spinner coat, a roll coat, a reverse roll coat, a kiss coat, a wheeler coat, a dip coat, and a silk screen. , Wire bar coating, flow coating, comma coating, flow coating, brush coating, spray coating, and other ordinary coating methods and transfer coating methods. Here, the transfer coating method is a method in which a coating film of the primer layer 3 is formed on a thin sheet (film substrate), and then the surface of the target layer in the decorative sheet is coated.

[Metal thin film layer 4]
The metal thin film layer 4 is a layer that is provided on the primer layer 3 and gives the decorative sheet a metallic design similar to that of the metal surface.

  The metal forming the metal thin film layer 4 is not particularly limited as long as it is a metal that can impart a metallic design to the decorative sheet. For example, tin, indium, chromium, aluminum, nickel, copper, silver, gold, platinum , Zinc, and alloys containing at least one of them. Among these, tin, indium, and chromium are preferable from the viewpoint of excellent extensibility. In addition, since the metal thin film layer 4 is formed of a metal having excellent extensibility, there is an advantage that cracks are hardly generated when the decorative sheet is three-dimensionally formed. The metal thin film layer 4 may be formed of one kind of metal or may be formed of two or more kinds of metals.

  Although the formation method in particular of the metal thin film layer 4 is not restrict | limited, From a viewpoint of providing a decorative metallic sheet with a high-quality and high-quality metallic design, for example, the vacuum evaporation method and sputtering method using said metal Vapor deposition methods such as ion plating are preferred. In particular, the vacuum deposition method is preferable in that it is low cost and causes little damage to the deposition target. The conditions for the vapor deposition may be appropriately set according to the melting temperature or the evaporation temperature of the metal to be used. In addition to the above evaporation method, a method of applying a paste containing the above metal, a plating method using the above metal, or the like can also be used.

  The thickness of the metal thin film layer 4 is not particularly limited, but the optical density (OD) value is preferably about 0.6 to 1.8, more preferably from the viewpoint of improving the designability and formability of the decorative sheet. Is about 0.8 to 1.4.

[Surface protective layer 5]
The surface protective layer 5 is a layer provided on the outermost surface of the decorative sheet as necessary for the purpose of enhancing the scratch resistance, weather resistance, etc. of the decorative sheet. Although the material which forms the surface protective layer 5 is not specifically limited, Usually, resin is used, Preferably ionizing radiation curable resin is used. Hereinafter, the case where the surface protective layer 5 is formed of an ionizing radiation curable resin will be described in detail.

(Ionizing radiation curable resin)
The ionizing radiation curable resin used for the formation of the surface protective layer 5 is a resin that crosslinks and cures when irradiated with ionizing radiation. Specifically, a polymerizable unsaturated bond or an epoxy group in the molecule. And a mixture of at least one of prepolymers, oligomers, monomers, and the like, as appropriate. Here, ionizing radiation means an electromagnetic wave or charged particle beam having an energy quantum capable of polymerizing or cross-linking molecules, and usually ultraviolet (UV) or electron beam (EB) is used. It also includes electromagnetic waves such as rays and γ rays, and charged particle rays such as α rays and ion rays. Among the ionizing radiation curable resins, the electron beam curable resin can be made solvent-free, does not require a photopolymerization initiator, and provides stable curing characteristics. Used for.

  As the monomer used as the ionizing radiation curable resin, a (meth) acrylate monomer having a radically polymerizable unsaturated group in the molecule is suitable, and a polyfunctional (meth) acrylate monomer is particularly preferable. The polyfunctional (meth) acrylate monomer may be a (meth) acrylate monomer having two or more polymerizable unsaturated bonds (bifunctional or more), preferably three or more (trifunctional or more) in the molecule. Specific examples of the polyfunctional (meth) acrylate include ethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, and 1,6-hexanediol di ( (Meth) acrylate, neopentyl glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, hydroxypivalate neopentyl glycol di (meth) acrylate, dicyclopentanyl di (meth) acrylate, caprolactone modified dicyclopentenyl di ( (Meth) acrylate, ethylene oxide-modified phosphoric acid di (meth) acrylate, allylated cyclohexyl di (meth) acrylate, isocyanurate di (meth) acrylate, trimethylolpropane tri (meth) acrylate , Ethylene oxide modified trimethylolpropane tri (meth) acrylate, dipentaerythritol tri (meth) acrylate, propionic acid modified dipentaerythritol tri (meth) acrylate, pentaerythritol tri (meth) acrylate, propylene oxide modified trimethylolpropane tri ( (Meth) acrylate, tris (acryloxyethyl) isocyanurate, propionic acid modified dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, ethylene oxide modified dipentaerythritol hexa (meth) acrylate, caprolactone modified dipentaerythritol Examples include hexa (meth) acrylate. These monomers may be used individually by 1 type, and may be used in combination of 2 or more type.

  The oligomer used as the ionizing radiation curable resin is preferably a (meth) acrylate oligomer having a radical polymerizable unsaturated group in the molecule, and more than two polymerizable unsaturated bonds in the molecule. A polyfunctional (meth) acrylate oligomer having (bifunctional or higher) is preferred. Examples of the polyfunctional (meth) acrylate oligomer include polycarbonate (meth) acrylate, acrylic silicone (meth) acrylate, urethane (meth) acrylate, epoxy (meth) acrylate, polyester (meth) acrylate, and polyether (meth) acrylate. , Polybutadiene (meth) acrylate, silicone (meth) acrylate, oligomer having a cationic polymerizable functional group in the molecule (for example, novolac type epoxy resin, bisphenol type epoxy resin, aliphatic vinyl ether, aromatic vinyl ether, etc.) . Here, the polycarbonate (meth) acrylate can be obtained, for example, by esterifying a polycarbonate polyol with (meth) acrylic acid. The acrylic silicone (meth) acrylate can be obtained by radical copolymerizing a silicone macromonomer with a (meth) acrylate monomer. Urethane (meth) acrylate can be obtained, for example, by esterifying a polyurethane oligomer obtained by reaction of polyether polyol or polyester polyol and a polyisocyanate compound with (meth) acrylic acid. Epoxy (meth) acrylate can be obtained, for example, by reacting (meth) acrylic acid with an oxirane ring of a relatively low molecular weight bisphenol type epoxy resin or novolak type epoxy resin and esterifying it. Also, a carboxyl-modified epoxy (meth) acrylate obtained by partially modifying this epoxy (meth) acrylate with a dibasic carboxylic acid anhydride can be used. Polyester (meth) acrylate is obtained by esterifying the hydroxyl group of a polyester oligomer having hydroxyl groups at both ends obtained by condensation of a polyvalent carboxylic acid and a polyhydric alcohol with (meth) acrylic acid, for example, or It can be obtained by esterifying the terminal hydroxyl group of an oligomer obtained by adding an alkylene oxide with (meth) acrylic acid. The polyether (meth) acrylate can be obtained by esterifying the hydroxyl group of the polyether polyol with (meth) acrylic acid. Polybutadiene (meth) acrylate can be obtained by adding (meth) acrylic acid to the side chain of the polybutadiene oligomer. Silicone (meth) acrylate can be obtained by adding (meth) (meth) acrylic acid to the terminal or side chain of silicone having a polysiloxane bond in the main chain. These oligomers may be used individually by 1 type, and may be used in combination of 2 or more type.

  These curable resins may be used alone or in a combination of two or more.

(Other additive ingredients)
Various additives can be blended in the ionizing radiation curable resin composition forming the surface protective layer 5 according to desired physical properties to be provided in the surface protective layer 5. Examples of the additive include a weather resistance improver such as an ultraviolet absorber and a light stabilizer, an abrasion resistance improver, a polymerization inhibitor, a crosslinking agent, an infrared absorber, an antistatic agent, an adhesion improver, a leveling agent, Examples include a thixotropic agent, a coupling agent, a plasticizer, an antifoaming agent, a filler, a solvent, and a colorant. These additives can be appropriately selected from those commonly used. In addition, as the ultraviolet absorber or light stabilizer, a reactive ultraviolet absorber or light stabilizer having a polymerizable group such as a (meth) acryloyl group in the molecule can be used.

(Thickness of the surface protective layer 5)
Although there is no restriction | limiting in particular about the thickness after hardening of the surface protective layer 5, For example, 1-1000 micrometers, Preferably it is 1-50 micrometers, More preferably, 1-30 micrometers is mentioned. When the thickness within such a range is satisfied, sufficient physical properties as a surface protective layer such as scratch resistance and weather resistance can be obtained, and ionizing radiation can be uniformly irradiated, so that it is uniformly cured. Can be made economically advantageous. Furthermore, since the thickness after the curing of the surface protective layer 5 satisfies the above range, the three-dimensional formability of the decorative sheet is further improved, so that it has high followability with respect to complicated three-dimensional shapes such as automotive interior applications. Can be obtained. As described above, the decorative sheet of the present invention can provide a sufficiently high three-dimensional formability even when the thickness of the surface protective layer 5 is larger than that of the conventional one. It is also useful as a decorative sheet for a member required for the vehicle, for example, a vehicle exterior part.

(Formation of surface protective layer 5)
The surface protective layer 5 is formed, for example, by preparing an ionizing radiation curable resin composition containing an ionizing radiation curable resin, applying it, and crosslinking and curing it. The viscosity of the ionizing radiation curable resin composition may be a viscosity that can form an uncured resin layer on the surface of the second primer layer 6, the metal thin film layer 4, and the like by a coating method described later.

  In the present invention, the prepared coating solution is applied to the gravure coat, the bar coat, the roll on the metal thin film layer 4 and a second primer layer 6 which will be described later if necessary so as to have the thickness. It coat | covers by well-known systems, such as a coat, a reverse roll coat, a comma coat, Preferably gravure coat, and forms an uncured resin layer.

  The uncured resin layer thus formed is irradiated with ionizing radiation such as electron beams and ultraviolet rays to cure the uncured resin layer, thereby forming the surface protective layer 5. Here, when an electron beam is used as the ionizing radiation, the acceleration voltage can be appropriately selected according to the resin to be used and the thickness of the layer, but usually includes an acceleration voltage of about 70 to 300 kV.

  In addition, in the electron beam irradiation, the transmission capability increases as the acceleration voltage increases. Therefore, when a resin that is easily deteriorated by electron beam irradiation is used under the surface protective layer 5, the electron beam transmission depth and the surface protection are used. The acceleration voltage is selected so that the thicknesses of the layers 5 are substantially equal. Thereby, the irradiation of the extra electron beam to the layer located under the surface protective layer 5 can be suppressed, and deterioration of each layer due to the excess electron beam can be minimized.

  The irradiation dose is preferably such that the crosslinking density of the surface protective layer 5 is saturated, and is usually selected in the range of 5 to 300 kGy (0.5 to 30 Mrad), preferably 10 to 50 kGy (1 to 5 Mrad).

  Furthermore, the electron beam source is not particularly limited. For example, various electron beam accelerators such as a Cockloft Walton type, a bandegraft type, a resonant transformer type, an insulated core transformer type, a linear type, a dynamitron type, and a high frequency type can be used. Can be used.

  When ultraviolet rays are used as the ionizing radiation, light rays including ultraviolet rays having a wavelength of 190 to 380 nm may be emitted. The ultraviolet ray source is not particularly limited, and examples thereof include a high pressure mercury lamp, a low pressure mercury lamp, a metal halide lamp, and a carbon arc lamp.

  By adding various additives to the surface protective layer 5 thus formed, a hard coat function, an antifogging coat function, an antifouling coating function, an antiglare coating function, an antireflection coating function, an ultraviolet shielding coating function, You may perform the process which provides functions, such as an infrared shielding coat function.

[Second primer layer 6]
The second primer layer 6 is a layer provided below the surface protective layer 5 as necessary for the purpose of improving the adhesion between the surface protective layer 5 and the layer located therebelow. The second primer layer 6 is, for example, between the surface protective layer 5 and the metal thin film layer 4, between the surface protective layer 5 and a color clear layer 7 described later, and between the surface protective layer 5 and a transparent film layer 9 described later. It is provided in between. The material for forming the second primer layer 6 is not particularly limited as long as it can improve the adhesion between these layers. For example, an acrylic resin, a polyurethane resin, an acrylic-urethane copolymer resin, Examples thereof include resins such as polyester resins.

  Although the thickness of the 2nd primer layer 6 is not specifically limited, Usually, about 0.5-2.5 micrometers, Preferably it is about 1-2 micrometers. The second primer layer 6 can be mixed with a colorant to adjust the color and improve the design, and further, a pattern from a design viewpoint can be formed. Although the formation method in particular of the 2nd primer layer 6 is not restrict | limited, For example, the surface of the layer located directly under the 2nd primer layer 6 among the metal thin film layer 4, the color clear layer 7, the transparent film layer 9, etc. The method etc. which apply | coat said resin above are mentioned. Further, the above-mentioned resin is applied on a separately prepared release sheet, and a layer such as a metal thin film layer 4 that is positioned below the second primer layer 6 in the decorative sheet from above the resin. And a method of forming the release sheet by peeling off the release sheet.

[Color clear layer 7]
The color clear layer 7 is a layer provided on the metal thin film layer 4 as necessary for the purpose of giving the metal tone of the metal thin film layer 4 a more glossy or the like. Although it does not specifically limit as a raw material which forms the color clear layer 7, For example, the transparent resin colored with the coloring agent etc. is mentioned. Although there is no restriction | limiting in particular as a coloring agent, For example, a coloring pigment, dye, etc. are mentioned. The transparent resin is not particularly limited, and examples thereof include acrylic resins, polyurethane resins, acrylic-urethane copolymer resins, and polyester resins. The thickness of the color clear layer 7 is not particularly limited, but is usually about 0.5 to 4 μm, preferably about 1 to 3 μm. The method for forming the color clear layer 7 is not particularly limited. For example, a layer located immediately below the color clear layer 7 among a third primer layer 8 described later, a transparent film layer 9 described later, a metal thin film layer 4 and the like. And a method of applying the above-described resin on the surface of a layer located immediately above the second color clear layer 7 such as the second primer layer 6.

[Third primer layer 8]
The third primer layer 8 is a layer provided under the color clear layer 7 as necessary for the purpose of improving the adhesion between the color clear layer 7 and the layer located therebelow. The third primer layer 8 is provided, for example, between the color clear layer 7 and the metal thin film layer 4 or between the color clear layer 7 and a transparent film layer 9 described later. The material for forming the third primer layer 8 is not particularly limited as long as it can improve the adhesion between these layers. For example, acrylic resin, polyurethane resin, acrylic-urethane copolymer resin, Examples thereof include resins such as polyester resins.

  Although the thickness of the 3rd primer layer 8 is not specifically limited, Usually, about 0.5-2.5 micrometers, Preferably it is about 1-2 micrometers. The third primer layer 8 can be mixed with a colorant to adjust the color and improve the design, and further, a pattern from a design viewpoint can be formed. The method for forming the third primer layer 8 is not particularly limited. For example, the surface of the color clear layer 7 or the transparent film layer 9 and the metal thin film layer 4 described later are directly below the third primer layer 8. And a method of applying the above-mentioned resin on the surface of the layer located in the region.

[Transparent film layer 9]
The transparent film layer 9 serves as a support that enhances the scratch resistance and weather resistance of the decorative sheet of the present invention and enhances moldability, and is a resin provided on the metal thin film layer 4 as necessary. It is a film. Since the moldability is improved by providing the transparent film layer 9, and the metal thin film layer 4 is less likely to crack when the decorative sheet is three-dimensionally formed, a metal other than tin, indium, chromium, which has excellent extensibility (for example, When forming the metal thin film layer 4 using aluminum etc., it is preferable to provide the transparent film layer 9. The resin film for forming the transparent film layer 9 is not particularly limited as long as it does not enhance the moldability of the decorative sheet and conceal the metallic design by the metal thin film layer 4. For example, polyethylene terephthalate (PET) , A polyester resin such as polyethylene naphthalate (PEN), or a film such as an acrylic resin. Although the thickness of the transparent film layer 9 is not specifically limited, Usually, about 15-200 micrometers, Preferably it is about 30-150 micrometers. The method for forming the transparent film layer 9 is not particularly limited. For example, the surface protective layer 5, the second primer layer 6, the color clear layer 7, the third primer layer 8, etc. are directly above the transparent film layer 9. And a method of laminating the above resin film on the surface of the layer located on the surface of the layer located immediately below the third primer layer 8 such as the metal thin film layer 4.

[Second adhesive layer 10]
The second adhesive layer 10 is a layer provided on the back surface of the base material layer 1 as necessary for the purpose of improving the adhesion and adhesion between the decorative sheet and the molding resin. The resin that forms the second adhesive layer 10 is not particularly limited as long as it can improve the adhesion and adhesion between the decorative sheet and the molding resin, for example, a thermoplastic resin or thermosetting. Resin is used. Examples of the thermoplastic resin include acrylic resin, acrylic-modified polyolefin resin, chlorinated polyolefin resin, vinyl chloride-vinyl acetate copolymer, thermoplastic urethane resin, thermoplastic polyester resin, polyamide resin, and rubber-based resin. . A thermoplastic resin may be used individually by 1 type, and may be used in combination of 2 or more types. Examples of the thermosetting resin include a urethane resin and an epoxy resin. A thermosetting resin may be used individually by 1 type, and may be used in combination of 2 or more types.

  Although the 2nd contact bonding layer 10 is not necessarily a required layer, applying the decorating sheet of this invention to the decorating method by sticking on the resin molded object prepared beforehand, such as the vacuum press-bonding method mentioned later. When assumed, it is preferable to be provided. When used in the vacuum pressure bonding method, it is preferable to form the adhesive layer 8 using a conventional resin that exhibits adhesiveness by pressurization or heating among the various resins described above.

  Although the thickness in particular of the 2nd contact bonding layer 10 is not restrict | limited, For example, about 0.1-30 micrometers, Preferably it is about 0.5-20 micrometers, More preferably, about 1-8 micrometers is mentioned.

2. Decorated resin molded product The decorated resin molded product of the present invention is formed by integrating a molded resin with the decorated sheet of the present invention. That is, the decorative resin molded product of the present invention comprises at least a molded resin layer, a base material layer 1, a primer layer 3, and a metal thin film layer 4 laminated in this order, and the primer layer 3 However, it contains the hardened | cured material of said resin whose glass transition point is -30 degreeC-80 degreeC, It is characterized by the above-mentioned. In the decorative resin molded product of the present invention, the above-described surface protective layer 5, the second primer layer 6, the color clear layer 7, the third primer layer 8, the transparent film layer 9, At least one layer such as the second adhesive layer 10 may be further provided.

  The decorative resin molded product of the present invention is produced by using the decorative sheet of the present invention, for example, by various injection molding methods such as insert molding, simultaneous injection molding, blow molding, and gas injection molding. The Among these injection molding methods, an insert molding method and an injection molding simultaneous decorating method are preferable. In addition, the decorative resin molded product of the present invention can be obtained by a decorative method of sticking the decorative sheet of the present invention on a three-dimensional resin molded body (molded resin layer) prepared in advance, such as a vacuum pressure bonding method. Can also be made.

  In the insert molding method, first, in the vacuum forming step, the decorative sheet of the present invention is vacuum formed (off-line pre-molding) into a molded product surface shape in advance by a vacuum forming die, and then an excess portion is trimmed as necessary. A molded sheet is obtained. This molded sheet is inserted into an injection mold, the injection mold is clamped, the resin in a fluid state is injected into the mold and solidified, and the decorative sheet is integrated on the outer surface of the resin molding simultaneously with the injection molding. By decorating, a decorative resin molded product is manufactured.

  More specifically, the decorative resin molded product of the present invention is manufactured by an insert molding method including the following steps.

A vacuum forming step of forming the decorative sheet of the present invention into a three-dimensional shape in advance by a vacuum forming die,
Trimming process to trim the excess part of the vacuum-decorated decorative sheet to obtain the molded sheet, and insert the molded sheet into the injection mold, close the injection mold, and inject the fluid resin into the injection mold Integration process to integrate the resin and the molded sheet.

  As described above, the decorative sheet of the present invention has high three-dimensional formability. For this reason, for example, when the decorative resin molded product has a curved portion, in at least one of the vacuum forming step and the integration step, the decorative sheet positioned in the curved portion is at a maximum draw ratio of 150% or more. Further, it may be stretched by about 200%. The upper limit of the maximum draw ratio is preferably about 250%.

  In the vacuum forming step in the insert molding method, the decorative sheet may be heated and molded. The heating temperature at this time is not particularly limited, and may be appropriately selected depending on the type of resin constituting the decorative sheet, the thickness of the decorative sheet, and the like. For example, when an ABS resin film is used as the base material layer If it exists, it can be about 100-250 degreeC normally, Preferably it can be about 130-200 degreeC. Moreover, in the integration step, the temperature of the resin in a fluid state is not particularly limited, but is usually about 180 to 320 ° C, preferably about 220 to 280 ° C.

  In addition, in the simultaneous injection molding decoration method, the decorative sheet of the present invention is placed in a female mold that also serves as a vacuum forming mold provided with a suction hole for injection molding, and preliminary molding (in-line preliminary molding) is performed with this female mold. After performing, the injection mold is clamped, the resin in a fluid state is injected into the mold, solidified, and the decorative sheet of the present invention is integrated on the outer surface of the resin molding simultaneously with the injection molding Thus, a decorative resin molded product is manufactured.

  More specifically, the decorative resin molded product of the present invention is manufactured by the simultaneous injection molding method including the following steps.

After the decorative sheet of the present invention is installed so that the surface of the base material layer of the decorative sheet faces the molding surface of the movable mold having a molding surface of a predetermined shape, the decorative sheet is heated, A pre-molding step of pre-molding the decorative sheet by softening and vacuum-sucking from the movable mold side and bringing the softened decorative sheet into close contact with the molding surface of the movable mold,
After the movable mold and the fixed mold having the decorative sheet adhered along the molding surface are clamped, the fluidized resin is injected into the cavity formed by both molds, and is solidified by filling. Forming a resin molded body, integrating the resin molded body and the decorative sheet, and integrating the decorative sheet, separating the movable mold from the fixed mold and resin molding Extraction process to remove the body.

  Similarly to the above-described insert molding method, also in the injection molding simultaneous decorating method, when the decorative resin molded product of the present invention has a curved portion, in at least one of the preliminary molding step and the integration step, You may extend | stretch the decorating sheet located in a curved part at the maximum draw ratio of 150% or more, and also about 200%. The upper limit of the maximum draw ratio is preferably about 250%.

  In the preforming step of the simultaneous injection molding method, the heating temperature of the decorative sheet is not particularly limited, and may be appropriately selected depending on the type of resin constituting the decorative sheet, the thickness of the decorative sheet, and the like. If a polyester resin film or an acrylic resin film is used as the base material layer, the temperature can usually be about 70 to 130 ° C. In the injection molding process, the temperature of the resin in the fluidized state is not particularly limited, but is usually about 180 to 320 ° C, preferably about 220 to 280 ° C.

  In the vacuum bonding method, first, the decorative sheet and the resin molded body of the first pressure chamber located on the upper side and the second vacuum chamber located on the lower side in the vacuum pressure bonding machine, the decorative sheet is the first. The vacuum chamber side is placed in a vacuum press so that the resin molded body is on the second vacuum chamber side, and the base material layer 1 side of the decorative sheet faces the resin molded body side, and the two vacuum chambers are in a vacuum state. To do. The resin molding is installed on a lifting platform that is provided on the second vacuum chamber side and can be moved up and down. Next, while pressurizing the first vacuum chamber, the molded body is pressed against the decorative sheet using an elevator, and the resin molded body is stretched while stretching the decorative sheet using the pressure difference between the two vacuum chambers. Adhere to the surface. Finally, the two vacuum chambers are opened to the atmospheric pressure, and the decorative resin molded product of the present invention can be obtained by trimming the excess portion of the decorative sheet as necessary.

  In the vacuum pressure bonding method, it is preferable to include a step of heating the decorative sheet in order to soften the decorative sheet and improve the formability before the step of pressing the molded body against the decorative sheet. The vacuum pressure bonding method provided with the said process may be especially called a vacuum thermocompression bonding method. Although the heating temperature in the said process should just be suitably selected with the kind of resin which comprises a decorating sheet, the thickness of a decorating sheet, etc., if it is a case where a polyester resin film or an acrylic resin film is used as a base material layer Usually, it can be about 60-200 degreeC.

  Similarly to the above-mentioned insert molding method and injection molding simultaneous decorating method, even in the vacuum pressure bonding method, when the decorative resin molded product of the present invention has a curved portion, the decorative sheet positioned in the curved portion has a maximum draw ratio. You may extend | stretch 150% or more, and also about 200%. The upper limit of the maximum draw ratio is preferably about 250%.

  In the decorative resin molded product of the present invention, the molded resin layer may be formed by selecting a resin according to the application. The resin forming the molded resin layer may be a thermoplastic resin or a thermosetting resin.

  Examples of the thermoplastic resin include polyolefin resins such as polyethylene and polypropylene, ABS resins, styrene resins, polycarbonate resins, acrylic resins, and vinyl chloride resins. These thermoplastic resins may be used individually by 1 type, and may be used in combination of 2 or more type.

  Moreover, as a thermosetting resin, a urethane resin, an epoxy resin, etc. are mentioned, for example. These thermosetting resins may be used individually by 1 type, and may be used in combination of 2 or more type.

  The decorative resin molded product of the present invention has high adhesion to each layer, can be molded into a complicated shape, and has a high-quality and high-quality metallic tone. For example, an interior material of a vehicle such as an automobile Or exterior materials; fittings such as window frames and door frames; interior materials of buildings such as walls, floors, and ceilings; housings of home appliances such as television receivers and air conditioners; containers and the like.

  Hereinafter, the present invention will be described in detail with reference to Examples and Comparative Examples. However, the present invention is not limited to the examples.

<Examples 1-10 and Comparative Examples 1-3>
(Preparation of decorative sheet)
An acrylic-urethane block copolymer resin is coated on a biaxially stretched polyethylene terephthalate sheet (E5001 manufactured by Toyobo Co., Ltd., thickness 25 μm) as a release sheet, and a transparent second primer layer having a thickness of 2 μm. Formed. Next, an acrylic-urethane block copolymer resin containing a colorant is applied on the second primer layer to form a color clear layer (thickness 2 μm) and a third primer layer (thickness 2 μm) in this order. did. Next, tin was vapor-deposited on the surface of the third primer layer to form a metal thin film layer having an optical density value (OD) of 1.2. Next, a primer layer (thickness 2 μm) having the composition and glass transition point (Tg) shown in Table 1 was formed on the metal thin film layer. In Examples 9 and 10, 30 parts by mass of a colorant (including titanium oxide and carbon black) having the same color as the metal thin film layer was added to 70 parts by mass of the resin of the primer layer. Next, an adhesive layer was formed on the primer layer by coating the resin shown in Table 1 to a thickness of 2 μm. Next, a sheet made of ABS resin having a thickness of 400 μm is brought into contact with the adhesive layer to form a base material layer, and a release layer / second primer layer / color clear layer / third primer layer / metal thin film layer A laminate in which / primer layer / adhesive layer / base material layer was laminated in this order was obtained. Next, a stainless steel metal plate with a satin pattern having an arithmetic average roughness Ra of 4.0 μm and a ten-point average roughness RzJIS of 16 μm is arranged on the base material layer side of the laminate, and on the release layer side. A stainless steel mirror plate with an arithmetic average roughness Ra of 0.05 μm was placed, and the laminate was hot press-molded with this metal plate and mirror plate. The conditions for hot press molding were a temperature of 150 ° C., a pressure of 0.5 MPa, and a heating / pressurization time of 10 minutes. Next, the release layer is peeled from the laminate, and an ionizing radiation curable resin is applied on the surface of the primer layer by gravure reverse so that the thickness after curing is 10 μm, and an uncured resin layer is formed. Formed. This uncured resin layer was irradiated with an electron beam having an acceleration voltage of 165 kV and an irradiation dose of 50 kGy (5 Mrad) to cure the uncured resin layer to form a surface protective layer. As described above, the base layer / adhesive layer / primer layer / metal thin film layer / third primer layer / color clear layer / second primer layer / surface protective layer having the structure shown in Table 1 Obtained a decorative sheet laminated in this order. As the ionizing radiation curable resin, a mixture of 80 parts by mass of a bifunctional polycarbonate acrylate (weight average molecular weight 10,000) and 20 parts by mass of a hexafunctional urethane acrylate oligomer (weight average molecular weight 6000) was used. In Comparative Example 3, no primer layer was provided.

(Formability evaluation test)
The decorative sheets of Examples 1 to 10 and Comparative Examples 1 to 3 were each heated to 160 ° C. with an infrared heater and softened. Next, using a vacuum forming mold, vacuum forming was performed under the condition that the maximum draw ratio was 150%, and a decorative sheet was formed so as to have an internal shape of the vacuum forming mold. Next, the decorative sheet was cooled and then released from the vacuum forming mold. No cracking or whitening was observed on the surface protective layer of the detached decorative sheet, and the one that followed the internal shape of the vacuum forming mold was evaluated as good (◯). Cracks and whitening were observed in the surface protective layer of the detached decorative sheet, and those that could not follow the internal shape of the vacuum forming mold were evaluated as having poor moldability (x). The results are shown in Table 1.

(Adhesion evaluation test)
The decorative sheets of Examples 1 to 10 and Comparative Examples 1 to 3 were vacuum formed by the same method as the above-described moldability evaluation test. Next, on the surface of the surface protective layer of the detached decorative sheet, 10 vertical and 10 horizontal grid-like cuts were made at intervals of 2 mm using a cutter knife. Next, a Nichiban cello tape (registered trademark) was pressure-bonded to the cut portion, and peeled off rapidly in the 90 ° direction. As a result of the adhesion evaluation test, a sheet having no peeling on the decorative sheet was evaluated as having good adhesion (◯). Although a very slight cut was found along the cut in the decorative sheet, it was evaluated that the adhesion was slightly good (Δ) when there was no practical problem. Those in which clear peeling was observed on the decorative sheet were evaluated as having poor adhesion (x). The results are shown in Table 1.

(Fade resistance evaluation test)
The decorative sheets of Examples 1 to 10 and Comparative Examples 1 to 3 were vacuum-formed by the same method as the above-described moldability evaluation test, and then allowed to stand for 72 hours in an environment of 60 ° C. and 90% humidity. Next, using a spectrocolorimeter (CM-3700d manufactured by Konica Minolta), color difference ΔE * ab (L * a * b color system of the International Commission on Illumination (CIE) defined in JIS Z8729-1994) Is measured). The color difference ΔE * ab is expressed by the following formula.
ΔE * ab = √ (ΔL *) 2+ (Δa *) 2+ (Δb *) 2
In addition, as a reference | standard of a color difference, the decorating sheet | seat of Examples 1-10 and Comparative Examples 1-3 before using for a fading resistance evaluation test was used, respectively. As a result of the color fading resistance evaluation test, when the color difference ΔE * ab is less than 3, the color fading is evaluated as small (◯), and when the color difference ΔE * ab is 3 or more and less than 5, the color fading is slightly large (Δ). When ΔE * ab was 5 or more, it was evaluated that the fading was large (×). The results are shown in Table 1.

(Heat resistance test of decorative resin molded products)
The decorative sheets of Examples 1 to 10 and Comparative Examples 1 to 3 were vacuum-formed by the same method as the above-described moldability evaluation test and used for injection molding. ABS resin [manufactured by Nippon A & L Co., Ltd., trade name “Clarastic MTH-2”] was used as the injection resin, and this was melted at 230 ° C. and then injected into the cavity. When the mold temperature reaches 30 ° C., the decorative resin molded product is taken out of the mold, and the decorative resin molding in which the decorative sheets of Examples 1 to 10 and Comparative Examples 1 to 3 are integrated with the injection resin, respectively. I got a product. Next, after leaving the obtained decorative resin molded product to stand for 168 hours in an environment of 100 ° C. and a humidity of 65%, respectively, the surface of the decorative resin molded product is visually observed, and the decorative sheet is peeled off. The presence or absence of was observed. ◯ if the decorative sheet is not peeled off at all; ○, the decorative sheet is slightly peeled off, but there is no practical problem at all; △, the case where there was peeling of a decoration sheet and there was a problem in practical use was evaluated as x. The results are shown in Table 1. Moreover, the surface photograph after the heat resistance test of the decorative resin molded product obtained using the decorative sheet of Example 1 and Comparative Example 1 is shown in FIGS. 5 and 6, respectively.

  In Table 1, “HDI” is 1,6-hexamethylene diisocyanate, and “XDI” is xylene-1,3-diisocyanate.

  As shown in Table 1, the addition of Examples 1 to 10 in which a primer layer containing a cured product of a resin having a glass transition point (Tg) of −30 ° C. to 80 ° C. was provided between the adhesive layer and the metal thin film layer. In the decorative sheet, it became clear that all were excellent in a moldability and adhesiveness, and the fading of the metal thin film layer was also suppressed. In the decorative sheets of Examples 9 and 10, the primer layers of the decorative sheets of Examples 3 and 9 are blended with a colorant having the same color as the metal thin film layer. The decorative sheet had better fading resistance. Furthermore, the decorative sheets of Examples 1 to 10 were peeled to the extent that no peeling was observed or no problem in practical use even when heated after making a decorative resin molded product. For example, as shown in the photograph of FIG. 5, in the decorative resin molded product obtained from the decorative sheet of Example 1, no peeling was observed even after the heat resistance test. On the other hand, although the primer layer was provided, in Comparative Example 1 using a resin having a glass transition point (Tg) higher than 80 ° C., the moldability is poor and peeling when the decorative resin molded product is heated is also caused. There was a problem in practical use. For example, as shown in the photograph of FIG. 6, the decorative resin molded product obtained from the decorative sheet of Comparative Example 1 peels off after the heat resistance test (the surface of the decorative sheet has a mountain shape). The base layer of the decorative sheet was exposed on the surface of the decorative resin molded product, and there was a problem in practical use. Moreover, although the primer layer was provided, in the comparative example 2 using the resin whose glass transition point (Tg) is smaller than -30 degreeC, it was inferior in the point of adhesiveness and anti-fading property. Furthermore, in Comparative Example 3 in which the primer layer was not provided, the fading of the metal thin film layer was large, and peeling when the decorative resin molded product was heated also had a practical problem.

DESCRIPTION OF SYMBOLS 1 ... Base material layer 2 ... Adhesive layer 3 ... Primer layer 4 ... Metal thin film layer 5 ... Surface protective layer 6 ... Second primer layer 7 ... Color clear layer 8 ... Third primer layer 9 ... Transparent film layer

Claims (15)

At least, a base material layer, a primer layer, and a metal thin film layer are composed of a laminated body laminated in this order,
The primer layer is a decorative sheet containing a cured product of a resin having a glass transition point of −30 ° C. to 80 ° C. Used for decorating resin molded products with curved parts,
The decorative sheet according to claim 1, wherein the curved portion has a shape that requires stretching at a maximum stretching ratio of 150% or more with respect to the decorative sheet.   The resin having a glass transition point of -30 ° C to 80 ° C is at least one selected from the group consisting of a polyester resin, a polyurethane resin, a polyacrylic resin, and a polyolefin resin. The decorative sheet described in 1. The resin having a glass transition point of −30 ° C. to 80 ° C. is a polyol resin,
The decorative sheet according to any one of claims 1 to 3, wherein the primer layer is formed of a cured product of the polyol resin and an isocyanate compound.   The decorative sheet according to claim 4, wherein the polyol resin is a polyester polyol.   The decorative sheet according to claim 4 or 5, wherein the isocyanate compound is an aliphatic isocyanate compound.   The decorative sheet according to any one of claims 1 to 6, further comprising an adhesive layer between the base material layer and the primer layer.   The decorative sheet according to claim 7, wherein the adhesive layer includes a chlorine-based resin.   The metal thin film layer is formed of at least one metal selected from the group consisting of tin, indium, chromium, aluminum, nickel, copper, silver, gold, platinum, zinc, and an alloy containing at least one of these. The decorative sheet according to any one of claims 1 to 8.   The decorative sheet according to any one of claims 1 to 9, wherein a surface protective layer is further laminated on the metal thin film layer.   The decorative sheet according to any one of claims 1 to 10, wherein a transparent film layer is further laminated on the metal thin film layer.   The decorative sheet according to any one of claims 1 to 11, wherein the primer layer further contains a colorant. At least a molded resin layer, a base material layer, a primer layer, and a laminated body in which a metal thin film layer is laminated in this order,
The primer layer is a decorative resin molded product including a cured product of a resin having a glass transition point of −30 ° C. to 80 ° C. A vacuum forming step in which the decorative sheet according to any one of claims 1 to 12 is previously formed into a three-dimensional shape by a vacuum forming die,
Trimming step of trimming an excess portion of the vacuum-decorated decorative sheet to obtain a molded sheet, and inserting the molded sheet into an injection mold, closing the injection mold, and injecting the resin in a fluid state into the injection mold An integration step of injecting the resin into the mold and integrating the resin and the molded sheet;
A method for producing a decorated resin molded product. The decorative resin molded product has a curved portion;
The method for producing a decorative resin molded product according to claim 14, wherein, in at least one of the vacuum forming step and the integration step, the decorative sheet positioned at the curved portion is stretched to a maximum draw ratio of 150% or more. .